Gosh, Rosemary Reeves is friendly. Of course, I knew she must be, because she won this year's AA friendliest landlady of the year award. But it's only when you arrive at Grey Cottage, a small stone cottage in the Cotswolds, where Rosemary's been welcoming guests for nearly 20 years, that you realise what this means. Within five minutes of my arrival, I'm sitting in the conservatory with a huge pot of coffee and a plate of homemade florentines. "Take one!" she beams.

But then this spread, along with the log fire, tea strainer and view of her immaculate garden with symmetrical rows of daffodils, is part of Rosemary's manifesto: attention to detail. "This is why I've got to where I've got to," she explains, gesturing at all the awards on the wall - AA breakfast and dinner award five-star rating; winner, The Good Hotel Guide Cesar 1999 - "because I go the extra yard." Rosemary would never serve her marmalade in a pot marked Co-op. "You take the trouble to put it in a china bowl!"

Not only is each guest bedroom equipped with Woods of Windsor soap, it's got a hairdryer and "beverage tray". Her freshly squeezed orange juice really is fresh, because she squeezes it herself first thing - and often at some ungodly hour. She always likes to be in her kitchen an hour and a half before her guests sit down to breakfast, to ensure things look just right. (She believes, quite passionately, that running a guest house is a public performance. "It's like being on stage all the time.") Plus, she has to listen to the weather forecast. Because if it's sunny, she serves heart-shaped fried bread, and if it's raining, it's ducks. Once she even served breakfast at four in the morning. "They were going to Gatwick airport - a good four-hour trip. I said, 'Right, I'll give you water, fruit, smoked salmon sandwiches, and I'll put them in the fridge for you. I'll put a note on the door, so you don't forget them. And I'll come and say goodbye in my dressing gown. Hope you don't mind.'"

Rosemary will even cook a three-course dinner, on request. "I ask guests if they want meat, fish or vegetarian. The rest is a surprise." She reads out a past menu: warm leak and gruyere tart with rocket salad, followed by roast halibut with mushroom sauce, rosti, carrots, courgettes and bacon, plus chocolate mousse with raspberries and organic ice-cream. Assembling the ingredients must have meant shopping for days. "But it's lovely!" she raves. "I'd rather do that than sit in an office."

A widow, and mother of two, Rosemary is as neatly packaged as the B&B she runs. Today she is wearing swishy trousers and high heels - a glamorous look most unlike the curlers and slippers worn by cliche B&B battleaxes. Not that she can't be chilly at times. Especially if guests are from London. "Typical Londoners are just so rude: no manners, no thank you please" - her eyes roll to denote the degree of their rudeness. "They come down here on a Friday, grumpy, hot and bothered, very demanding, and that's when I put my navy dress on and become rather imperious."

Rosemary grew up in Dublin, where her father was director of Imperial Tobacco. She says she learned to be so spick and span from a Swiss finishing school, where her mother, a former model, sent her, aged 18. "Not a posh one, but one run by the Swiss state. You had to scrub loos and buff up Swiss army uniforms to perfection." There, she also learned how to make super-light shortcrust pastry and wrap up presents. She is bilingual (German) and her first job was with a brick import/export business. She travelled to international trade shows, and learned how to deal with different types. (She prides herself on being able to work people out from the first telephone call, which is why she refuses to book online - "so dead".)

In 1965 she married the boss, and had two sons, but they separated in 1972. Then, in 1974, she married Andrew, one of her father's managers. After he took early retirement the couple moved to Grey Cottage, in 1979. (Her husband liked horse racing, and Cheltenham is only 20 miles away.) They started the B&B by accident in 1984. "We were having our Sunday lunch and there was a Danish family on bikes outside on the road, and the girl had got her jeans caught in the mudguard. I don't know what possessed me, but I went out and said, 'Do come in. You're all very welcome for supper and have a bed.' They were going to the youth hostel at Slimbridge but never got there. When they were leaving, they said, this is no bed and breakfast, this is a bed and banquet. So we decided then and there to open a B&B."

Business has grown from one bedroom, one bathroom, and one pair of sheets ("I stripped the bed and put it in the machine and stuck it in the dryer, and then back on the bed") to three bedrooms, and four bathrooms (three en suite) plus several sheets, mostly from M&S's elite Supima range. The only visitors Rosemary doesn't welcome are toddlers: "They draw on the walls and wee in the bed."

Since her husband died in 2000 she does everything - cooking, accounts, shopping, banking (although she has a gardener and someone who irons). She says the downside is you always have to be in a good mood, and it's hard to find the time to visit the dentist, let alone see friends. "I get more Christmas cards from my visitors than I do from friends." But she has no plans to retire. "I suppose it is a dedication," she smiles, "and I am very dedicated."